G6PC1 and neonatal abstinence syndrome: On mRNA (Supplementary Fig. S4C) and protein expression analysis (Fig. 4C,D), G6Pase and other key enzymes [fructose-1, 6-bisphosphatase (FBPase), and phosphoenolpyruvate carboxykinase (PEPCK)] showed significant downregulation during 4-MEI and 4-MEI+NAS treatment and significant upregulation during NAS treatment compared to untreated control.